package com.hmdp.utils;

import org.apache.tomcat.jni.Local;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
//id生成器
public class RedisIdWorker {
    //开始时间戳
    private static final long BEGIN_TIMESTAMP = 1735689600L;
    //序列号的位数
    private static final long COUNT_BITS = 32;

    private StringRedisTemplate stringRedisTemplate;
    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }
    public long nextId(String keyPrefix) {
        //1.生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp= nowSecond-BEGIN_TIMESTAMP;
        //2.生成序列号
        //2.1获取当天日期，精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        //2.2自增长  icr:表示他是自增Id
        Long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
        //3.拼接返回  符号位+时间戳+序列号
        return timestamp << COUNT_BITS | count;
    }
}
